Art of anchorage



Dec. 1, 1931. H, RQSENBERG 1,834,871

ART OF ANCHORAGE Original Filed Jan. 27. 1928 glwuenfoz Patented Dec. 1, 1931 EEYMAN ROSENBERG,

PATENT OFFICE OF NEW YORK, N. Y.

ART OF ANCHORAGE Original application filed January 27, 1928, Serial No.

1929. Serial This invention relates to improvements in the art of anchorage devices of the character adapted for anchorage in or to metal work and for the securing of separate sheets of metal work together, and more particularly to such devices as are adapted to cause the material of the metal Work to flow in a cold condition to a position relative to the anchorage device for resisting withdrawal thereof.

For purposes of -illustration, but not of restriction, the present invention relates to improvements in that class of anchorage devices under which fall the subjects matter of the following United States Letters Patent granted to me: No. 1,299,232, dated April 1, 1919;

No. 1,411,184, dated March 28, 1922; No. 1,465,148, dated August 14, 1923; No. 1,482,-

151, dated January 29, 1924; No. 1,485,202,

dated February 26, 1924; No. 1,526,182, dated February 10, 1925, and No. 1,545,471, dated July 7, 1925.

This application is a division of my copending application Serial No. 249,900, filed January 27, 1928, issued July 14, 1931, as

Patent No. 1,814,966.

The primary object in View is provision for facility in variation of the form, shape, or appearance of a portion or portions of the anchorage device subsequent to the hardening of the work-entering means of such anchorage device.

With this and further objects in view as will in part hereinafter become apparent and in part bestated, the invention comprises an anchorage device having a hardened Workenteringpart and abutton-receiving headhaving a soft portion adapted for deformation to aid in location of orto otherwise contribute to the anchorage of'the button.

The invention still further comprises certain other novel constructions, combinations, and arrangements of parts, and certain other novel steps and combinations of steps in the art of producing such constructions, combinations, and arrangements of parts as will subsequently specified and claimed.

In the accompanying drawings,.

Figure 1 is a sectional elevation of an anv chora'ge device embodying the features of the 249,900., Divided and this application filed Kay 10,

In the use of anchorage devices of the type disclosed by my prior patent above cited,

especially where a finely finished job is required, such, for example, as the securing of plush, tapestry, and like fine fabrics to the frame and other parts of the interior of closed automobile bodies, the problem has arisen to prevent the exposure of what may appear to be either a screw head or a rivet head. It has been proposed, for instance, to cover the exposed terminus of the anchorage devices securing the fabrics with a snap button or like concealing expedient. According to my prior patents the anchorage devices are marketed with ribs or threads hardened so as to enter soft iron or soft steel substantially without injury to the ribs orfthreads, and as a convenient and inexpensive mode of production, the anchorage devices are customarily hardened to provide the requisite hardening of the thread or rib, and this, of course, includes a hardening of the ends of the anchorage device which, accordingly, resist any subsequent manipulation. Attachments applied to either end of any such anchorage device must, therefore, be secured thereto without modification of the respective end portion of the anchorage device. The present invention contemplatesproviding all of the advantages of the improved hardened thread or hardened rib anchorage device while providing available means forming part of such device susceptible of modification in contour to facilitate subsequent treatment of the anchorage device for application of a terminal cover and for other purposes as hereinafter indicated.

The nature of the invention will be better understood by detailed reference to the accompanying drawings, in Figure 1 of which is illustrated a pin of the type now'commonly known as a metallic drive screw (as distinguished from a wood drive screw), the drive screw being of the form and nature set' forth in my United States Letters Patent N 0. 1,482,151, and comprising a body or root diameter 1 having outstanding ribs 2 extending along the body and spirally about the same at a relatively high pitch, the ribs being hardened sufficiently for entering metal,

' such as soft iron or soft steel, substantially without injury to the ribs, and being pro- .mportioned, spaced, and located for causing the pilot 3 is of greater diameter than thediameter of the body 1 so as to afford an interlocking shoulder 18 presented upward or toward the head 19 across and closing each of the' valleys between ribs 2.

The pin or anchorage; device, consisting essentially of the parts 1 and 2, isca-se-hardened by preference for providing the requiredhardness of the ribs 2. The case-hardening process is preferably carried out in the usual manner of cyanide case-hardening, so that the pilot 3 is also hardened when'the ribs and surface of the'body or root diameter 1 are hardened. Care is exercised to harden the threads to a degree suflicient to enable them to I cut or enter metal, such as soft iron or soft middle area 0 the ribbed portion of root disteel, substantially without injury "to the threads, without. hardening to the point of brittleness. It is possible, of course, to hard en only the ribs and leave the head 19 soft, by

a quenching process restricted to pilot 3 and the ribbed areas of the root diameter 1. That is to say, the head 19 may be covered with heat insulatin material, and the pilot and ameter 1 may be placed in position to intersect the arc of an electrical furnace, and then the e .50 ench may be applied only to the pilot and middle portions 0 the root diameterl until the required tempering and hardening of the pilot 3 and ribs 2 is effected without appreciably hardening the head 19. Th s is, of course, an involved, delicate, and d1ilicult process and will not ordinar ly be preferred although well within the Intent and scopev of .the present invention. A better commercial expedient in the matter of pro-.

ducing a hardened pilot and'hardened rib or hardened thread body consists'in case-hard suing the entire anchorage devlce, mcluding the body 1, ribs 2, pilot 3, and head 19,"by the cganide process, or otherwise as preferred in Afterward, the head 19 is ant e usual way.

nealed by dipping into molten metal to draw the temper and is then allowed to cool slowly to leave the head 19 soft while the ribs .and surface of the root diameter 1 remain hardened. The conditions under which the temper drawing process is carried out maybe varied substantially as well known to those skilled in the art, but for illustrative purposes, the dippingof the head 19'into molten metal (such as lead or solder) at a temperature of approximately 600 F. will effect the result desired. Or the temper may be drawn from the head 19 by introduction into a highly heatedbath of tempering oil subsequent to the regular case-hardening process. Annealing in the oil may beaccomplished at lower temperature than stated'for the molten metal bath, but the parts must be 'held in the bath proportionally longer.

A further and very effective method of obtaining-pins or drive screws embodying the present invention comprises first electro-plating the parts to be left soft and then casehardening as usualla theelectro-plated parts resisting entry of t ecyanide into .the pores of the metal and thereby causing the electroplated part to remain soft. For example, when the drive screw or pin is completed except for the hardening process, the body or root diameter and ribs of the pin and any other part to be hardened may be coated with:

shellac or other resisting substance, the balance of the pin being then pickled or otherwise thoroughly cleaned. The drive screw'is then introduced into the electro-plating bath and plated on that part or those parts not protected by shellac. Other plating resisting means may be used. than an added lacquer or coating of course, as, for instance, the oil and otherforeign matter accumulated during manufacture under some conditions will ade-' quately resist plating. Copper is preferably employed as the plating metal, but, of course, any other acceptable metal may be used. The

drive screw is then ready for t e case-hardening operation, which may be carried out without any variation from the regular process of producing drive screws completely case-hardened. But the result will be a hardenedthread product with a soft head or other soft part or parts according to the extent of the electr'o-plating.

- hus the finished anchorage device has the appearance and functional capacity 1n every detail of the anchorage device disclosed in "my said United States Letters Patent No.

1,482,151,except that the head 19 is not hardened. It should be borne in mind that the terms hard and soft herein employedare intended to have that significance regularly accepted by those skilled in metal work ing, and particularly in the working of iron and steel wherein hardened iron and hard? ened steel are well known and distinct, fr m soft iron or soft steel. 1

The head 19 is substantially of conventioniao a1 contour for receiving the conventional snap button 20, which may have any fanciful or beautifying finish. In the common commercial forms of such devices, the snap button is removably secured by spring-arms 21 engaging an overhanging shoulder 22 of the head 19 for retaining the button 20 firmly in place, except when the button is subjected to a very substantial withdrawing stress, under which the springs 21 will give sufficiently to allow the button to be removed. To facilitate accurate seating of'the button 20, it is customary to rovide an annulus or washer 23 located at t e upper or outer extremity of the body or root diameter 1, and heretofore customarily held in place by radial serrations outstanding from the body of the anchorage device or from the lower reduced portion of the head and biting into the inner perimeter of the washer or annulus 23.

However, with the present invention utilized, the head 19 is sufficiently soft to be altered in contour after the completion of the hardening process for the ribs 2, and, therefore, the head is provided with a cylindrical portion 24 proportionedto receive the annu lus 23, whereupon material of the head 21 is stamped out into a flange 25 underlying portions of the annulus 23 and securely retaining the same in place to provide the limiting and guiding abutment for the inner extremities of the springs 21. Formation of flange 25 reduces portion 24 to an annular groove. In applying the fastener to work, the application ismade in the usual manner by a hammer blow delivered to the head 19 after the pilot 3 has been introduced into the aperture formed in the work to receive it. The annulus 23 will have been applied at the factory where the anchorage device was made, and is, therefore, in place at the time the anchorage device is driven into the work. As soon as the anchorage device is seated, or at any time thereafter, the operator may snap one of the buttons 20 over the head 19 and the work is finished.

It should be obvious that in every instance wherea portion of the anchorage device is made or left soft and is, therefore, susceptible of modification in appearance or in function or both, that fact in no sense interferes with the regular functioning of the anchorage device for anchorage purposes, and that fact also does' not demand the actual modification of which the part is capable. Also,the advantages and utilities indicated and set forth above in the provision of a soft part or parts to an anchorage device having hardened parts indicate some 'of the desirable reasons for the present invention, others being apparent.

The utility of the soft part of an otherwise hardened anchorage device has in the foregoing discussionsbeen largely assumed to lend adaptability to change in form, func-.

tion or appearance, but obviously the soft part may e provided for other uses and purposes, such as increasing the bearing on the exposed portions of the work.

While the invention is herein indicated for use with metal work, such as soft iron or soft steel, and in other hard substances, such as fiber, bakelite, hard rubber, and the like, the present invention is not limited to such illustrative instances.

What is claimed is:

1. An anchorage device comprising a metal pin having a hardened anchorage portion adapted to be anchored in metal work incident to its hardened condition and a soft head for the pin proportioned to snugly receive and cooperate with a snap fastener, a portion of the soft head being flanged by cold-fiowing incident to its soft condition to produce a circumferential groove for accommodating and sustaining a part cooperating with such snap fastener, the soft condition of the head enabling such cold flow after the hardening of the anchorage portion.

2. An anchorage device comprising a metal pin having a hardened anchorage portion adapted to be anchored in metal work incident to its hardened condition and a soft head for the pin proportioned to snugly receive and cooperate with a snap fastener, the head being provided with a reduced portion adjacent the anchorage part, which reduced portion leaves an overhanging, peripheral shoulder adapted to receive and interlock with parts of the snap fastener, the reduced portion of the head being cold-flowed peripherally incident to its soft condition about the terminus of the reduced portion remote from the overhanging shoulder to accommodate and sustain a washer in position to cooperate with the snap fastener engaging the head, the soft condition of the head enabling such coldflow after the hardening of the anchorage portion.

In testimony whereof I affix my signature.

- HEYMAN ROSENBERG. 

